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Why IPv6 is so complicated

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Re: Why IPv6 is so complicated

#501

Post by mixmastamyk »

throw0101a wrote: post #486
mixmastamyk wrote: post #446

Earlier quoted context omitted.

On extra byte shoved in a reserved field would have created 256 internets. That's two more for big countries and another for each small country and other planets. Then write in hex so addresses are shorter, require dhcp/sec etc, solved. My proposal for IPv7. ;-)

> On extra byte shoved in a reserved field would have created 256 internets. Ah yes, the old IPv4 with 'just' adding more address byte(s) idea (you "IPv7"): So you have to update DNS to create new resource record types ("A" is hard-coded to 32-bits) to support the new longer addresses, and have all user-land code start asking for, using, and understanding the new record replies. Just like with IPv6. (A lot of legacy…

Don’t need dual stack, just one updated. Further addresses would have stayed readable and there wouldn’t be two bindings per adapter etc.

When typing addresses first byte is optional and defaults to zero. Problem solved. I saw this strategy work well with Brazilian phone numbers.

Partial rollout is not a problem to me at home but multiple address gibberish is.

Re: Why IPv6 is so complicated

#502

Post by MaKey »

speedgoose wrote: post #471
MaKey wrote: post #393

Earlier quoted context omitted.

Which european cloud provider is it?

The latest dedibox from Scaleway.

Here is the documentation from Scaleway on IPv6: https://www.scaleway.com/en/docs/dedibox-ipv6/quickstart/

The first step is to request an IPv6 prefix. Did you do that?

Re: Why IPv6 is so complicated

#503

Post by speedgoose »

MaKey wrote: post #502
speedgoose wrote: post #471

Earlier quoted context omitted.

The latest dedibox from Scaleway.

Here is the documentation from Scaleway on IPv6: https://www.scaleway.com/en/docs/dedibox-ipv6/quickstart/ The first step is to request an IPv6 prefix. Did you do that?

I did not read this documentation and I did not request a prefix. Thanks for the hint.

IPv4 worked without any required action so I moved on. I wanted to use this example for my frustrations toward IPv6.

Re: Why IPv6 is so complicated

#504

Post by zadikian »

Ekaros wrote: post #496
zadikian wrote: post #492

Earlier quoted context omitted.

No, the idea is you can turn v6 on/off, but doing so only changes the packet format and nothing else at first. There's no separate place to configure v6-specific settings because there are none. You use the same address, routes, DHCP, NAT, DNS, etc as v4, but you're limited to 32-bit addrs at first. The point is to just get people off v4. Once v6 has reached enough adoption, you can turn off v4. Those who want to kee…

I don't see why anyone would change all the bits you actually need to change for some nebulous future gains. Still have to deal with new sockets and new routing decisions at least. To not really gain much from new features. To me it looks like something that would have gained nearly no actual adoption outside some toy examples. Later you will need to anyway get new DNS, DHCP(or alternative) and so on.

That's a legit concern. If that's not interesting enough to the kind of user that wants all-new v6, instead start from today where some users are on the new v6 network, and say they added the 4:: prefix as a way to pick up the kind of user that doesn't want to change much. They'd still be compatible eventually. Though the reason I was thinking 4:: from the start would've been attractive enough is, a lot of people did use 6to4 and other halfway measures despite having no immediate gain.

Today's DNS6 DHCP6 etc are totally incompatible with v4. 4:: buys backwards-compatibility. Each can be updated to support longer addrs without caring whether you use it with v4 or v6.

Re: Why IPv6 is so complicated

#505

Post by zadikian »

tardedmeme wrote: post #468
zadikian wrote: post #462

Earlier quoted context omitted.

Those are regions that have a lot of v6 support alongside v4, not v6-only.

Most v4 support is through a gateway. You can't tell the user's IP address from the wrong side of the gateway, for example - only the gateway's address. The user isn't on v4, the gateway is.

Yeah, so you still reach the user, it's just probably less efficient than the all-v6 route.

Edit: Oh, you mean if they want unsolicited inbound traffic? Sure, but that's only a thing for services. I mean you can have a default-allow firewall to home devices but really shouldn't.

Re: Why IPv6 is so complicated

#506

Post by throw0101a »

zadikian wrote: post #497
throw0101a wrote: post #487

Earlier quoted context omitted.

> I want something:x.x.x.x to get routed to me over v6 if I had x.x.x.x in v4, as the default and recommended way of contacting an ipv6 host, without needing additional config or middleboxes. Anyone with an IPv4 automatically got a 'free' IPv6 allocation: > For any 32-bit global IPv4 address that is assigned to a host, a 48-bit 6to4 IPv6 prefix can be constructed for use by that host (and if applicable the network be…

Owning 192.0.2.4 in v4 didn't really give you 2002:192.0.2.4 in v6, as in v6 packets can't reach you that way. If someone sent a v6 packet there, some router on their side would intercept it and relay as v4. Aside from this still relying on v4, it was very unreliable in practice because of uncertainty around what v6 route is taken to the relay. There's an RFC somewhere that looked at this in hindsight.

AIUI, you encapsulate anything to 2002:192.0.2.4/48 into an IPv4 packet with "41" in the protocol field (as opposed to 6 (TCP) or 17 (UDP)) and send it to 192.0.2.4. 192.0.2.4 would then work as the relay and extract the IPv6 traffic and handle it.

* https://en.wikipedia.org/wiki/IPv4#Protocol

* https://simple.wikipedia.org/wiki/Protocol_41

Re: Why IPv6 is so complicated

#507

Post by throw0101a »

mixmastamyk wrote: post #501
throw0101a wrote: post #486

Earlier quoted context omitted.

> On extra byte shoved in a reserved field would have created 256 internets. Ah yes, the old IPv4 with 'just' adding more address byte(s) idea (you "IPv7"): So you have to update DNS to create new resource record types ("A" is hard-coded to 32-bits) to support the new longer addresses, and have all user-land code start asking for, using, and understanding the new record replies. Just like with IPv6. (A lot of legacy…

Don’t need dual stack, just one updated. Further addresses would have stayed readable and there wouldn’t be two bindings per adapter etc. When typing addresses first byte is optional and defaults to zero. Problem solved. I saw this strategy work well with Brazilian phone numbers. Partial rollout is not a problem to me at home but multiple address gibberish is.

A node having 198.51.100.42 and 7.198.51.100.42 (or 198.51.100.42.7) is dual-stack: one address is for the IPv4 protocol and other is for the IPv7 the protocol.

You need different DNS records for IPv7 and new API calls. You need Happy Eyeballs so that if 7.198.51.100.42 fails your application falls back to 198.51.100.42. It's the exact same situation.

Re: Why IPv6 is so complicated

#508

Post by zadikian »

da_chicken wrote: post #485
kstrauser wrote: post #390

Earlier quoted context omitted.

> Everyone who dislikes IPv6 doesn't know how NAT works and thinks it's the same as a firewall. It would be easier if IPvOld proponents didn't keep saying that it is. Seriously, every time this topic comes up, at least one person expresses horror at the idea of running IPv6 without a firewall, unlike their safely NAT-firewalled IPv4 setup. > There's absolutely no downside whatsoever to being publicly addressable. I w…

Everyone likes to use DNS. How do I use DNS on my home network to set up my home router? It's the same problem as TLS certificates on web interfaces for infrastructure. And the commercial solution is going to be "pay us a subscription fee so your home device can get an Internet management interface on top of all the egregious data collection".

The home solution is supposed to be mDNS. I just checked right now, my mDNS isn't working on my LAN, idk why.

Re: Why IPv6 is so complicated

#509

Post by zadikian »

zadikian wrote: post #299

I disagree that it would've been just as hard anyway. The people who say "I just wanted v4 with more bits" have a point that most of these arguments completely ignore, but this one touches on it: Actually, we tried that: the "IPv4-Compatible IPv6 address" format was defined in [RFC3513] but deprecated by [RFC4291] because it turned out to be of no practical use for coexistence or transition. The practical use would'v…

Want to add, it's not too late to do this on top of the ipv6 we have today.

Re: Why IPv6 is so complicated

#510

Post by simoncion »

ninkendo wrote: post #431
simoncion wrote: post #346

Earlier quoted context omitted.

> IME nothing pays attention to when you set a flag to not do autonomous addressing. When I unset the Autonomous flag, Linux does the right thing, at least on the systems I have at hand. Android does the right thing. My Playstation 5 does the right thing. I'd be shocked if Windows doesn't do the right thing. While I wouldn't be surprised to hear that Apple devices absolutely do the wrong thing -given Apple's long his…

Y’know I see you in every thread about IPv6 and you have this terrible habit of completely ignoring the actual point someone is trying to make and bogging straight down into the minutiae of some technical detail instead. I will stipulate that it’s possible to configure a network so that clients don’t set up their own addresses and use only DHCP. I will stipulate that I fucked up the configuration the last time I trie…

> ...you have this terrible habit of completely ignoring the actual point someone is trying to make and bogging straight down into the minutiae of some technical detail instead. ... [w]ould you maybe get past that and look at my actual point, which is that multiple addresses is the expected and default behavior of IPv6...

Here's your comment's [0] second paragraph:

  I think this is the biggest change with IPv6: that a machine’s IP addresses is no longer its identity, and you can’t easily predict what address will be used when connecting somewhere. IP-based access control becomes impossible (not that it was ever a great idea in the first place), reverse DNS lookups become irrelevant, seeing IP’s in logs no longer tells you “what machine connected here”, it’s overall a big change in mental model.
An attentive reader notes that I did not object to your comment's first paragraph. [1] Such a reader also notes that in your reply to me you both double down on the claim that it's impossible to centrally control what IPv6 addresses a host has, and go on to claim that even if you could it would be undesirable to do so.

[0] https://news.ycombinator.com/item?id=47987900>

[1] "The changes to Ethernet lookup mandate that you have a link-local address in addition to your “real” address, and this starts the ball rolling on the idea that machines have multiple IP addresses in general. Which makes privacy addresses commonplace, ULA+GUA addresses on the same machine, etc."

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